AÇIK HAVA KOŞULLARININ ODUN DAYANIMINA ETKİSİ

Öz

Herhangi bir koruyucu kullanmadan, uygun tür seçilmeden kullanılan ağaç malzemenin fiziki ve ekonomik ömrü sınırlıdır. Ağaç malzemenin çeşitli teknikler yardımıyla koruyucu kimyasal maddelerle muamele edilerek kullanım süresinin uzatılması ve niteliklerinin iyileştirilmesi ise önemli bir gelişmedir. Açık hava etkisi ise çoğunlukla rutubet etkileri ve sıcaklık değişmelerinden kaynaklanan fiziksel olaylarla, fotokimyasal reaksiyonları kapsayan uzun süreli karmaşık bir süreçtir. Açık hava şartlarında kullanılacak ahşap malzemenin türünün, direnç özelliklerinin değişiminin, dayanım süresinin ve maruz kalınan zararlı faktörlerin bilinmesi

gerekmektedir. Ahşap malzemenin açık hava şartlarında bozunma ve tahrip olması organik ve inorganik olmaktadır. Organik faktörler çürüme, küf, bakteri ve böcekleri, inorganik faktörler ise güneş, rüzgar, su, bazı kimyasallar ve ateşi kapsamaktadır. Odun üzerinde oluşacak çeşitli enerji formlarının nispi etkilerinde de farklı ağaç türleri itibarıyla değişim görülmektedir. Odundaki kimyasal değişmeler, renk değişmeleri, mikroskobik değişmeler, fiziksel değişmeler ve biyolojik faktörlerin sebep olduğu değişmeler belirli zaman faktörü sonunda oluşmaktadır. Boya, yüzey işlem maddeleri ve derine nüfus eden koruyucu maddeler odunu uzun süreli korumakta ve dış mekanlarda uygun şartlar da dayanım sürelerini arttırmaktadır. Açık hava etkisine karşı korunma çalışmaların da en iyi korumayı boyanın sağladığı, en az korumanın transparan verniklerden sağlandığı belirtilmektedir.

Anahtar Kelimeler

• Açık Hava Koşulları,Yıkanma,Boyalar,Yüzey İşlemleri

THE EFFECTS OF WEATHERİNG ON WOOD STRENGTH

Abstract

The use of wooden materials without preservatives and improper selection of the species shorten their service life. It is such an important development that impregnation of wooden materials using various techniques with preservatives helps extending service life and increasing the quality. Weathering is such a long and complicated process that includes physical changes along with moisture and change of temperature and photochemical reactions. It is necessary to investigate the characteristics of wooden materials used outdoors such as species, change of strength, service life and exposure to harmful factors. Destruction of wooden materials used outdoors can be the result of either organic or inorganic factors. Organic factors are fungi, mould and mildew, bacteria and insects. Inorganic factors are sunlight, wind, water, various chemicals and fire. Variation of destruction caused by the factors mentioned above differs from wood species. Chemical, microscopic, and physical changes, coloration and discoloration, caused by biological factors happen after certain periods of time. Paints, wood finishes and preservatives protect wood for a very long time and prolong their service life. According to studies, the highest protection can be achieved by using paints and the lowest is by transparent varnishes.

Keywords

• The Effects of Weathering,Paints,Leaching,Finishing

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